Infections pose a serious threat to cancer patients in chemotherapy. Prompt diagnosis and treatment is of paramount importance as infections may be life-threatening in immune-compromised individuals. Traditionally, the C-reactive protein (CRP) has been used as a marker of infection. However, the CRP is also often elevated in cancer patients and as a marker CRP may be unreliable in cancer patients. Other markers for infection includes procalcitonin which has been showed to be of some value for the diagnose of bacterial infections.